Not everybody likes 10x eco...it gets to a point where it is excessive...what you're talking about just feeds whales even more. I currently play in a universe that is x8 and we have several players who are producing more than 11 billion metal per day. At x10 eco we're talking 13.75 billion a day...at 10.67 eco 14.6 billion. As is we're at a point where gameforge is giving out astro tolkens in consecutive years. Are we really interested in handing people a couple new planets every year?
A more realistic idea might be to have a new event. Something that temporarily changes eco, research, fleet speeds of universes. At that point, you could do a 50x eco event for 24 hours or a 20x eco for 2 days or whatever other scenarios you can come up with. Of course it needs to come with a caveat that packages aren't affected by the event.